Process for manufacturing material suitable for wall covering, putty, or the like



" ire nunowotr, or BERLIN-CEARLOTTENBURG, s nni/ra mnssrenon r0 nnnnrnoosnosn anrrnnensnrnscnanm (sear sonwnn n e-nsnnrsonar'r); or rennin,

GERMANY, A oonrona'rrort.

misses.

No Drawing.

To all whomit may concern: Be it known that I, KUNO ing at Kantstrasse 85, Berlin-Charlottenburg, Germany, have invented certain new and useful Improvements in a Process-for Manufacturing Material Suitable for ."Vall Covering, Putty or the like (for which I have filed applications in Germany,March 17, 1919;.Austria, Sept. 9,1919, Hungary, Feb. 25, 1920), of which the following is a specification. e

The hitherto known processes for the manufacture of magnesia cement may be classed as follows: i l 1. Processes yielding a ohloridic cement, 2. Processes yielding a cement free from chloride, and

3. Processes in which, in the place of cal cmed magnesite, a calcinedartliicial magnesite is employed as a basic element for the cement. 1

N ow it is well known that articles formed of a magnesia cement of this kind are not weather proof but rathercrack, swell up, and in some cases instead of becoming harder, turn softer and softer. Asan attendant phenomenon of the physical change taking place within said mass, an efliorescence is formed on the surface thereof. Thus, for instance, the cement known as Sorel cement, an aqueous magnesium oxychloride, embodies the undesirable property of being apt to be decomposed by water, and that rapidly by means of. hot water, and slowly by cold water; even at atemperature of 30 C. fissures make their appearance.

Now by means of this present invention, with the addition, it may be, of filling substances, there isthe possibility of producing out of magnesite and a lye of chloride of magnesium a material suitable for wall coverings, glaziers putty or similar purposes. a

The invention is based on the recognition that the magnesium oxide obtained on the decomposition of combinations of magnesium, such for example as MgOO Mg(NO Mg(OH) will always, chemically considered, correspond to the formula MgO, but from a physical chemical Viewpoint will be different accordingto the initial conditions existing in each case. Thus, for ex- Specification of Letters Patent.

Won, residgranulous structure.

rnoenss non nenuraornarne narnnmr. SUITABIE raga- COVERING" PUT, I OR'THELIKE." i I p Patented June 6, 1922 Application filed. August 1,1921. Serial No. 489,077.

ample, the MgO derivedfrom MgCO is a white, amorphous mass, while the "MgO derived from Mg(NO,) showsa firm As a result of the varying density of the mass, which difiers accordingto the particular nature ofc the mass started with, there are createdconditions which, owing to the diverse surface formation, will also in the course of the subsequent chemicalphysical transformation with aid of a solution ofv chloride of magma sium yield, from case to case ,.differentfinal products. The fact is that these are. colloid chemical conditions which crop up in the various stages of condensation.

It has further been d1scovered,thatiin the production of MgO, as a base for a magnesium cement, the action of the temperature plays avery importantpart. For while powerfully glowed MgCO, will yield MgO which combined with H O, will pass over exceedingly slowly into Mg(Ol-I),, this transformation will take place at afar greater speed, provided the; -MgCO has been but gently glowed. As for the Mg(OH), for its part being thereupon gently, glowed there will arise an which, in its-physical-chemical nature .will considerably differ from that originally obtained. The conditions will befoundto be analogous on; starting with a condensed magnesite-which, as known, is a typical Based on the results thus gained by experience, and with the view to obtaining a useful IV g0, and one always capable of reproduction, in full accordance (with this present invention, the method resorted/to consists I, in condensed magnesite being weakly or gently glowed, dry slaking :the

mitted to a glowing operation is rendered less reactive by dry slaking and re-calcina tion.

However, also as regards the employ of lye of chloride of magnesium in combination with magnesite, the present invention reposes on entirely novel discoveries, since it has been foundthat for the production of a magnesite cement use cannot be immediately made of a lye of chloride of magnesium, that is to say of a solution of Mgtll 6(H O), in water. but only of such a lye of chloride of magnesium which in addition contains Mg(UH) and. nggg loidal distribution. The intensity of the concentration of said lye of chloride of magnesium has been found to be of vast importance for the production of a cement of chloride of magnesium. In accordance with my invention, crystallized chloride of magnesium is dissolved in water, and thereupon boiled until an intensely concentrated lye of magnesium of about 36 B. or more is produced, which is then filtered.

It thus follows that the novel process of obtaining a material suitable alike as a wall covering for glaziers putty, or the like, essentially consists, on the one hand, in condensed magnesite being weakly glowed preferably at a temperature of 600 to 7 00 C., being dry slaked after having cooled down, and the product thus obtained being preferably calcined at a temperature of 800 (1, then ground and strained. On the other hand, crystallized aqueous chloride of magnesium is dissolved in water and boiled for a length of time sufficient until the filtrate possesses a density of about 36 or more, whereupon it is filtered. The two products thus obtained, namely the oxide of magnesium and the magnesium lye, are then mixed until a homogeneous plastic mass has formed.

The respective proportions of lye and oxide of magnesium may, for instance, be so chosen, that gr. of lye of chloride of magnesium of 362 are mixed with 4:0 of oxide of magnesium. This mass which is subjected to hardening for about 18 to 20 hrs, will prove durable, and will constitute either per se or else in combination with a filling material such as clay, kieselguhr, etc. a substance suitable'for manifold purposes, say, as wall covering, glaziers putty, cutlers lute, and the like. In the case of the addition of filling materials then, subject to the present invention, such substances only must be added, which are in a thorin colougl'ily purified colloidal state. The em ploy of colloidal filling materials, which is known per se secures to the present improved process the benefit that the advantages gained will also be retained to a high degree on adding filling materials. On employing other filling materials, there will be produced substances which are not weather proof, and which crack, and efiloresce, because the materials added are not in the state of disintegration required for the colloidal-chemical processes taking place during the hardening operation. Having now fully set forth and ascertained the nature of my invention, and the particular purpose for which it is destined, what I claim is:

1. In a process of manufacturing material suitable for wall covering, putty and the like, the following steps: Weakly glowing condensed magnesite, dry slaking the same after cooling and then calcining the resulting product; dissolving crystallized chloride of magnesium in water, boiling until an intensely concentrated solution has formed and then filtering said solution; finally mix :ing the two products resulting, that is, the oxide of magnesium and the magnesium chloride solution.

2. In a process of manufacturing material suitable for wall covering, puttyand the like, the following steps: glowing condensed magnesite at a temperature of from 600 to 700 (3., dry slaking the same after cooling and then glowing the product at about 800 0.; dissolving crystallized chloride of magnesium in water and then concentrating the solution to about 30 B. or more; finally, mixing the oxide of magnesium andthe magnesium chloride solution. In a process of manufacturing material suitable for wall covering, putty and the.

like, the following steps: densed magnesite to a glowing operation and after cooling dry slaking and then calcining the same; dissolving magnesium chloride in water and then boiling and consubjccting concentrating the same; mixing the oxide of magnesium and magnesium chloride solu tion thus obtained, and adding thoroughly purified colloidal substances as filling materials to the mixture.

In testimony whereof I aflix my signature in presence of two witnesses.

Dr. EGAN Lanesrnn, MAX. Annnns. 

